Pope Francis quotes GKC

Recently Pope Francis quoted Chesterton, as reported in this link on the Vatican's website (Well, an allusion, as far as I can make out for sure, not a direct quote, but still...):

http://www.vatican.va/holy_father/francesco/cotidie/2013/en/papa-francesco-cotidie_20131205_words-mad_en.html

Pope Francis then recalled the prophet Isaiah who, in the first Reading (26:1-6) says: “Trust in the Lord for ever, for the Lord is an everlasting rock”. “The rock is Jesus Christ, the rock is the Lord. Our word is forceful, it bestows life, it continues on, it can tolerate any attack if this word is rooted in Jesus Christ”. However, he said, “a Christian word whose life-giving roots are not grounded in a person, in Jesus Christ, is a Christian word without Christ. And Christian words without Christ deceive, they do harm”.

The Pontiff then quoted the English author G. K. Chesterton (1874-1936), when speaking about heresy once said that a heresy is a truth, a word, a truth gone mad. “When Christian words lack Christ, they begin to head down the road of madness”. The prophet Isaiah, he added, clearly describes the nature of this madness. He says: “The Lord is an everlasting rock. For he has brought low the inhabitants of the height, the lofty city” (26:4-5). “The inhabitants of the height. A Christian word without Christ leads to vanity, to self assuredness, to pride, and to power for power’s sake. And the Lord brings these people low”.

Presumably the Pope is making reference is to the third chapter of Orthodoxy:

The modern world is not evil; in some ways the modern world is far too good. It is full of wild and wasted virtues. When a religious scheme is shattered (as Christianity was shattered at the Reformation), it is not merely the vices that are let loose. The vices are, indeed, let loose, and they wander and do damage. But the virtues are let loose also; and the virtues wander more wildly, and the virtues do more terrible damage. The modern world is full of the old Christian virtues gone mad. The virtues have gone mad because they have been isolated from each other and are wandering alone. Thus some scientists care for truth; and their truth is pitiless. Thus some humanitarians only care for pity; and their pity (I am sorry to say) is often untruthful. For example, Mr. Blatchford attacks Christianity because he is mad on one Christian virtue: the merely mystical and almost irrational virtue of charity. He has a strange idea that he will make it easier to forgive sins by saying that there are no sins to forgive. Mr. Blatchford is not only an early Christian, he is the only early Christian who ought really to have been eaten by lions. For in his case the pagan accusation is really true: his mercy would mean mere anarchy. He really is the enemy of the human race -- because he is so human. At the other extreme, we may take the acrid realist, who has deliberately killed in himself all human pleasure in happy tales or in the healing of the heart. Torquemada tortured people physically for the sake of moral truth. Zola tortured people morally for the sake of physical truth. But in Torquemada's time there was at least a system that could to some extent make righteousness and peace kiss each other. Now they do not even bow.